Chronic rumination exhibited by some emotionally distubed or retarded children threatens life, retards physical, social and emotional development, and places a severe strain on the child's caregivers. Available therapies are of limited value and practicality. Lemon juice therapy presents an alternative. Recently, two children were treated. Rumination quickly stopped, and development accelerated. The treatment required filling the child's mouth with lemon juice when rumination occurs, a procedure easily learned by the children's caregivers. The objective of this research is to further evaluate lemon juice therapy with ruminators of varying ages in residential care. Success in eliminating rumination, accelerating development, and obtaining positive changes in the children's living environments will be evaluated. Procedures used to train the caregivers to use the treatment will be described. The effectiveness of the treatment will be assessed using a controlled, single subject, research design. Therapy will be extended sequentially to the children in a multiple baseline, experimental design across subjects. The children's post-therapy progress will be described by measures of rumination, development, and adult interaction with the children obtained via daily behavioral observations, developmental scales, weight gain, and questionnaires. Paraprofessional staff will be trained using instruction, modeling, and feedback.